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Class test 5: 5.8.2020

Total questions: 10

Worksheet time: 7mins

Name
Class
Date
1.

LASING action depends on

a)

Spontaneous emission

b)

Stimulated emission

c)

Spontaneous emission followed by stimulated emissions

d)

Absorption of radiation

2.

Semiconductor materials produces light

a)

Silicon

b)

Gallium

c)

Germanium

d)

None of the above

3.

Combination of semiconductors that emits blue colour in LED

a)

Gallium Arsenide

b)

Gallium Nitrite

c)

Gallium Arsenide and Phosphide

d)

Gallium Phosphide

4.

In a LED light output is directly proportional to the ---------------------------------

(a)  

5.

The switching speed of LEDs is in terms of

a)

1nsec

b)

1msec

c)

1microsec

d)

1sec

6.

To turn on the LED in common anode type 7 segment display, LED is to be connected to Supply or to Ground?

(a)  

7.

If a laser diodes emits light in a direction parallel to the PV junction plane then laser diode is called

a)

Edge – emitting LASER diode

b)

Surface Emitting LASER diodes

c)

Plane Emitting LASER diode

d)

Diagonal emitting LASER diode

8.

Lasers are used for a variety of applications. Which of the following is an example of areas that lasers are used.

a)

commercial fields

b)

scientific fields

c)

medical applications

d)

all of the above

9.

To form a LASER diode Gallium Arsenide (GaAs) like materials are to be doped with

a)

Aluminium

b)

Silicon

c)

Selenium

d)

All the above

10.

Which is the most commonly advertised types of laser surgery today?

a)

laser dermatology

b)

laser skin resurfacing

c)

LASIK

d)

tattoo removal